1. Field of the Invention
This invention relates to a fuel tank for automotive vehicles which is capable of preventing evaporative fuel generated therein from being emitted into the atmosphere during refueling.
2. Prior Art
A fuel tank with a liquid seal device has already been proposed by Japanese Laid-Open Utility Model Publication (Kokai) No. 63-137033, in which a bent filler pipe is employed and the liquid seal device blocks up the filler pipe with fuel (gasoline) supplied through a tank filler port and trapped in a bent portion of the filler pipe to thereby prevent evaporative fuel from being emitted into the atmosphere.
More specifically, the filler pipe has a fuel outlet port device formed of a pipe bent into the shape of a character J and connected to a main body of the filler pipe, whereby fuel is trapped in the fuel outlet port device to prevent evaporative fuel generated within the fuel tank from entering the filler pipe.
Further, the prior art publication discloses a check valve provided in an open end of the filler pipe projecting into the fuel tank for preventing evaporative fuel from being blown out of the tank filler port via the filler pipe.
However, the fuel outlet port device of the prior art fuel tank is prepared by merely bending a filler pipe without modification of the shape of the open end of the filler pipe located within the fuel tank. Consequently, refueling at a high flow rate causes an increase in flow resistance to fuel supplied, which impedes smooth refueling. Moreover, since the fuel outlet port device is formed of a bent portion of the pipe, the filler pipe has to be largely projected into the fuel tank, e.g. as shown in FIG. 1 of the above-mentioned publication, which results in a lower degree of freedom of arrangement of related component parts.
Further, according to the prior art, the open end of the fuel outlet port device is directed toward a float valve provided at an end of an evaporative fuel-guiding pipe opening into the fuel tank. Consequently, fuel flowing into the fuel tank from the fuel outlet port device can impinge on the float valve, thereby causing the same to temporarily close the evaporative fuel-guiding pipe. This causes a temporary rise in pressure within the fuel tank to trigger an auto-stop function of a filler gun to stop refueling before the refueling is completed, thereby impeding smooth refueling.